Precipitating and desalting high-salt wastewater recycling process

A high-salt wastewater and process technology, applied in the direction of flocculation/sedimentation water/sewage treatment, water pollutants, multi-stage water treatment, etc., can solve problems such as interference with chloride ion removal, limited operation effect, and chemical consumption, etc., to achieve process operation Stable and reliable, low operating cost, and reduced corrosiveness of effluent

Pending Publication Date: 2020-01-10
SHANGHAI UNIVERSITY OF ELECTRIC POWER
View PDF6 Cites 22 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The technical process is simple, but there are two unfavorable factors in practical application that will limit its operation effect
One is that there are impurity ions such as sulfate and magnesium in the wastewater, which compete with the addition of precipitant to form magnesium-aluminum hydrotalcite or ettringite (Ca 6 Al 2 (OH) 12 (SO 4 ) 3 26H 2 O), causing unnecessary consumption of chemicals and interfering with the removal of chloride ions; second, excessive concentration of chloride ions in high-salt wastewater will produce a large amount of sludge, and it is difficult to effectively separate solids and liquids in traditional single sedimentation tanks

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Precipitating and desalting high-salt wastewater recycling process
  • Precipitating and desalting high-salt wastewater recycling process
  • Precipitating and desalting high-salt wastewater recycling process

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0059] In this example, the wastewater to be treated is the flue gas desulfurization wastewater of an inland thermal power plant. figure 1 As shown in the process flow, the equipment involved includes a preliminary desulfurization tank 1, a deep desalination tank 4, a sedimentation tank 7, and a dehydrator 15 connected in series, wherein the preliminary desulfurization tank 1 is connected to the first dosing tank 2 and the first flocculation dosing Box 3, deep desalination tank 4 is connected to the second dosing tank 5 and the third dosing tank 6, the sedimentation tank 7 is connected to the second flocculation dosing tank 8, and the clear liquid outlet of the dehydrator 15 is connected to the slurry in the sedimentation tank 7 through the return pipe Entrance.

[0060] The specific treatment process of using the above system to treat wastewater is as follows: the pretreated desulfurization wastewater is passed into the preliminary desulfurization tank 1, and the agent A is a...

Embodiment 2

[0064] The nanofiltration concentrated solution of a waste incineration plant contains 5071 mg / L of sulfate radicals and 6794 mg / L of chloride ions. The content is 3270mg / L of chloride ion, using figure 1 Process flow shown. The specific treatment process is as follows: the pretreated smoke washing wastewater is passed into the preliminary sulfur removal tank 1, and the agent A is added through the first chemical dosing box 2 (the agent A is calcium hydroxide, and its dosage is the mole of sulfate radical in water. Concentration 10 times) make it react to generate calcium sulfate precipitation, add flocculant A through the first flocculation dosing box 3 simultaneously to improve sedimentation performance (flocculant A is FeSO4 , the dosage is 5g / L); the hydraulic retention time in the primary desulfurization tank 1 is 2h. The precipitate obtained from the solid-liquid separation in the preliminary desulfurization tank 1 is comprehensively utilized as gypsum after subsequent ...

Embodiment 3

[0067] In this example, the waste water to be treated is the flue gas desulfurization waste water of a Linhai thermal power plant. image 3 The process flow shown, the equipment involved includes a preliminary desulfurization tank 1, a deep desalination tank 4, and a dehydrator 15 connected in series, wherein the preliminary desulfurization tank 1 is connected to the first dosing tank 2 and the first flocculation dosing tank 3, and the depth is The desalination pond 4 is connected with the second medicine adding box 5 and the third medicine adding box 6 .

[0068] The specific treatment process is as follows: the pretreated desulfurization wastewater is passed into the preliminary desulfurization tank 1, and the agent A is added through the first chemical dosing box 2 to make it react to form calcium sulfate precipitation, and at the same time, it is injected through the first flocculation chemical dosing box 3 Add flocculant A to improve the sedimentation performance; the hyd...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention relates to a high-salt wastewater precipitation desalting recycling process, which is a two-stage process and comprises the following steps: a first stage: removing sulfur by a calcium sulfate method, to be more specific, synchronously removing sulfate radicals and divalent metal salts by adding lime to a calcium sulfate method sulfur removal unit; and a second stage: performing deepsulfur removal and chlorine removal, to be more specific, simultaneously deeply removing the sulfate radicals and chloride ions by adding lime and aluminum salt in a deep sulfur removal and chlorineremoval unit. Compared with the prior art, the multi-stage precipitation desalting process provided by the invention considers the problem of efficient sludge dewatering while treating sewage, improves the removal efficiency and reduces the treatment cost.

Description

technical field [0001] The invention relates to the technical field of environmental protection and rational utilization of water resources, in particular to a new multi-stage sedimentation and desalination process for high-salt wastewater. Background technique [0002] High-salt wastewater generally refers to wastewater with a total salt content ≥ 1%, and the salts mainly include Cl - , NO 3 - , SO 4 2- 、Na + , Ca 2+ , Mg 2+ Wait. The production of high-salt wastewater in China accounts for 5% of the total wastewater, mainly from coal chemical industry, seawater desalination, wet flue gas desulfurization and other fields, and is still growing at a rate of 2% every year. The discharge of high-salt wastewater will increase the salinity and hardness of the water body, threaten human health, increase the cost of softening treatment, and cause corrosion of industrial equipment. Therefore, foreign countries have long been concerned about the impact of high-salt wastewate...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C02F1/52C02F1/56C02F101/12
CPCC02F1/5236C02F1/56C02F2101/12C02F2301/08
Inventor 周振明强辛仪郭家明赵晓丹孙东奇叶小芳杜卓玲安莹
Owner SHANGHAI UNIVERSITY OF ELECTRIC POWER
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap